U.S. Pat. No. 4,608,649 (the '649 patent), granted Aug. 26, 1986 to J. W. Davis et al, describes a technique for constructing DCVS circuits in which clusters of active differentially associated pairs of devices (e.g. CMOS transistor gates) and circuits formed by interconnecting the devices are constructed in essentially a single process. Each cluster is customized to contain only the devices required to construct a particular circuit for performing an operation representing a particular logical function.
The design of such circuits tends to be rather complex, and difficult to modify once finalized. Thus, circuits produced by such processes tend to have long and costly development cycles and rather high manufacturing costs.
The present invention seeks to provide a device topology and process for constructing DCVS circuits of comparable density but in less time and at less cost than would be required using the technique of the above '649 patent.